netlink: bug fix: wrong size was calculated for vfinfo list blob

The wrong size was being calculated for vfinfo.  In one case, it was over-
calculating using nlmsg_total_size on attrs, in another case, it was
under-calculating by assuming ifla_vf_* structs are packed together, but
each struct is it's own attr w/ hdr (and padding).

Signed-off-by: Scott Feldman <scofeldm@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 7331bb2..1a2af24 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -650,11 +650,12 @@
 	if (dev->dev.parent && dev_is_pci(dev->dev.parent)) {
 
 		int num_vfs = dev_num_vf(dev->dev.parent);
-		size_t size = nlmsg_total_size(sizeof(struct nlattr));
-		size += nlmsg_total_size(num_vfs * sizeof(struct nlattr));
-		size += num_vfs * (sizeof(struct ifla_vf_mac) +
-				  sizeof(struct ifla_vf_vlan) +
-				  sizeof(struct ifla_vf_tx_rate));
+		size_t size = nla_total_size(sizeof(struct nlattr));
+		size += nla_total_size(num_vfs * sizeof(struct nlattr));
+		size += num_vfs *
+			(nla_total_size(sizeof(struct ifla_vf_mac)) +
+			 nla_total_size(sizeof(struct ifla_vf_vlan)) +
+			 nla_total_size(sizeof(struct ifla_vf_tx_rate)));
 		return size;
 	} else
 		return 0;